Re: [PATCH v3 7/7] qemu-options.hx: Support "auto" for accel SMMUv3 properties

[Nathan Chen <nathanc@nvidia.com>]

On 5/14/2026 9:19 AM, Shameer Kolothum Thodi wrote:
> 
>> -----Original Message-----
>> From: Nathan Chen<nathanc@nvidia.com>
>> Sent: 12 May 2026 20:35
>> To:qemu-arm@nongnu.org;qemu-devel@nongnu.org
>> Cc: Eric Auger<eric.auger@redhat.com>; Peter Maydell
>> <peter.maydell@linaro.org>; Philippe Mathieu-Daudé<philmd@linaro.org>;
>> Zhao Liu<zhao1.liu@intel.com>; Matt Ochs<mochs@nvidia.com>; Nicolin
>> Chen<nicolinc@nvidia.com>; Shameer Kolothum Thodi
>> <skolothumtho@nvidia.com>; Nathan Chen<nathanc@nvidia.com>
>> Subject: [PATCH v3 7/7] qemu-options.hx: Support "auto" for accel SMMUv3
>> properties
>>
>> From: Nathan Chen<nathanc@nvidia.com>
>>
>> Update documentation now that "auto" is supported for accelerated
>> SMMUv3 properties.
>>
>> Signed-off-by: Nathan Chen<nathanc@nvidia.com>
>> ---
>>   qemu-options.hx | 25 +++++++++++++++++++------
>>   1 file changed, 19 insertions(+), 6 deletions(-)
>>
>> diff --git a/qemu-options.hx b/qemu-options.hx index
>> 96ae41f787..46b02a1bb3 100644
>> --- a/qemu-options.hx
>> +++ b/qemu-options.hx
>> @@ -1291,30 +1291,43 @@ SRST
>>           Enabling accel configures the host SMMUv3 in nested mode to support
>>           vfio-pci passthrough.
>>
>> -     The following options are available when accel=on.
>> -     Note: 'auto' mode is not currently supported.
>> +     The following options will be set to auto by default if not manually
>> +     set. When accel=on and these properties are set to auto, the value is
>> +     derived from the host SMMUv3 capabilities via IOMMU_GET_HW_INFO.
>> With
>> +     accel=on, this requires at least one cold-plugged vfio-pci device; if
>> +     none is present at machine init, QEMU will abort.
>>
>> -    ``ril=on|off`` (default: on)
>> +     If accel=off, auto values resolve to the non-accel defaults given below.
>> +
>> +    ``ril=on|off|auto`` (default: auto)
>>           Support for Range Invalidation, which allows the SMMUv3 driver to
>>           invalidate TLB entries for a range of IOVAs at once instead of issuing
>>           separate commands to invalidate each page. Must match with host
>> SMMUv3
>>           Range Invalidation support.
>> +        - With accel=on, auto means the value is automatically derived from the
>> host SMMU.
>> +        - With accel=off, auto is resolved to 'on'.
> If the intention here is to have bullet points for above, you might need a blank
> line before "-" . Please see how this gets rendered in html format and
> adjust.
> 
> Same for others below.
Ok, I will confirm the render and update accordingly on the next revision.

Thanks,
Nathan